Former Everton junior Mustafi's dreams were dashed when the Coach cut him from the final 23 that will go to Brazil.
"Of course Mustafi, [Marcel] Schmelzer and [Kevin] Volland are disappointed," he told dfb.de.
"I understand that because they all had a reason to be confident of going to Brazil.
"[Assistant] Hans Flick and I have personally informed all the players of our decision. But they will all have the chance to go to big tournaments in the future."
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